Which is better, China Mobile Tietong or China Mobile Chengdu Research Institute?

China Mobile Tietong and China Mobile Chengdu Research Institute are both good. China Mobile Tietong is a subsidiary of China Mobile Communications Group, which is mainly responsible for the construction and operation of fixed communication networks, providing fixed telephone, broadband and other services. China Mobile Chengdu Research Institute is a research institution under China Mobile Communications Group, which is committed to promoting the research and innovation of mobile communication technology, including the research and development in the fields of 5G, Internet of Things and cloud computing. So China Mobile Tietong and China Mobile Chengdu Research Institute are both good. China Mobile Tietong and China Mobile Chengdu Research Institute are two entities under China Mobile Communications Group, which are engaged in different fields of business.